Coating of insulators



Nov. 2, 1943. E. H. FISCHER COATING OF INSULATORS Filed Jilly 31, 1940 7 Sheets-Sheet 1 INVENT R Z'yeyeE/ciez:

ATTO Y WITNESSES:

Nov. ,2,- 1943. E; H. FISCHER 2,333,557 I COATING 0F INSULAI'ORS I Filed July 31 1 94o 7 Sheets- Sheet 2 I 75 Vac won urce WITNESSES: INVENTOR fiiffiyez fizs'cen 7; BY I 4. ATTOEY Nov. 2, 1943. E. H. FISCHER 2,333,557

' COATING 0F INSULATORS Filed July 51, 1940 7 Sheets-Sheet 5 ATTOR Y Nov. 2, 1943. E. H. FISC HER comma 0F INSULATORS '7 Sheets-Sheet '7 Filed July 31, 1940 INVENT ii z e/zefifi sr wt ATTOR Y WITNESSES: (211M 9,3,; M

suppression of radio interference.

ducting coating is applied to the insulator sur-, face at and adjacent to the points of contact withconductors and other metallic parts or mem-' Patented Nov. 2. 1.943

comma or INSULATORS I 7 Eugene H. Fischer nerry. Pa., assignor to Westinghouse Electric & Manufacturing Company, East Pittsburgh, Pa; a corporation of Pennsylvania Application July 31', 1940, Serial No. 348,804

The present invention relates to the coating of ceramic bodies and it has particular relation to the application to electrical insulating bodies of coatings which are to cover only mined portion thereof.

In the electrical insulator art, it has becomecommon practice to apply'a conducting coating to portions of insulators, generally in addition tothe regular glaze, for such purposes as the This conbers toreduce electrical discharge to the insulator surface. The coating material employed is preferably a liquid of the oomposition described in Hunt U. S. Patent No. 1,973,076, while further consideration of the principles involved may be found in Patents Nos. 1,997,688 and 1,997,686.

Insulators oi the pin-type, for example, are generally provided with a coating of this type-at .most eflicient and effective extent of the conducting coating is readily determinable. Since application of the coating to any greater amount of the surface results in a w'aste of material and may impair the eflectiveness of the insulator, the industry has encountered the problem of aca predeterv ,the upper surface to cover the conductor and'tiewire groove portions and also within the pin hole. For each type and size of insulator, the v insulators.

aninsulator previously picked up by it to a predetermined depth in coating liquid disposed in a constant level receptacle disposed elsewhere I along the"periphe'ry of the rotating 'member.

Thus, the device continuously-coats the desired u portions of the insulators at a rapid rate and it' is only necessary for an operator to place the articles on the conveyor at some point in its travel and removethem from the rotating mem:- her after completion of the coating process. It

.will appear evident that the invention is not limited to any particular type of insulator and may be used to coat articles with materials other than the conducting or semi-conducting compound previously described.

It is accordingly an object of the present invention to provide an improved method and means for applying a coating to ceramic bodies.

It is another object of the invention to previde improved apparatus for coating a predetermined portion of the surface of electrical Another object of the invention is to provide improved apparatus for coating recessesin eleccurately and uniformly applying this material to the proper surface portion of the insulator in n inexpensive and eflicient manner.

According to one embodimentoi the present invention, an intermittently driven conveyor is provided to carry insulatorsplaced thereon in sequence to a pair of predetermined'stationary positions serving as operating stations. At the iirst'of these stations a tube is automatically lowered into the pin hole of an inverted insulator and a measured amount of coating material is passed through the tube to fill the pin hole to the height to which a coating is desired therein. The'tube is then connected to a vacuum source in the top'of the coating receptacle andthe coating material in excess of that adhering to the surface of the pin hole is withdrawn from the bottom thereof. The tube is next withdrawn from the pin hole after which the insulator is moved to the second station. A m'ulti-armed member which is intermittently rotated in synchronism with the conveyor moves downwardly as'each insulator reaches this second position and grips the same it to remove it from the conveyor. At. time another arm of the conveyor dips I a pin type insulator parts broken away;

trical insulators to a predetermined height.

A further object of the invention is to provide apparatus for. automatically applying coating material to the pin holes and a portion of the outside surfaces ofelectrical insulators of the pintype.

Other objects and advantages of the invention will appear from the following 'detafled description taken in conjunction with the accompanying drawings in which:

- Figure 1 is a side elevational view of apparatus built in accordance with the present invention; Fig. 2 is a plan view of the apparatus of Fig. 1 "Fig. 3 is an enlarged vertical sectional view of illustrating a type of glaze coating which may be applied thereto by means of the invention;

Fig. 4' is an enlarged side elevational view of the driving and of enlarged view,

Fig. 5 is an and cam mechanism of the intermittentdriving of the apparatus; C

Fig. 6 is an end view partly in section and at an enlarged scale, of the-apparatus of Figs. '1

and 2;

Fig. '7 is van enlarged vertical sectional view taken along the line VII-VII of Fig. 2;

Fig. 8- is an enlarged view,

and partiy in side elevation of the pin hole glaz the apparatus oi Fig. 1 with partly in section Q partly in section I ing equipment taken from the direction of the,

right hand end of Fig. 1;

Fig. 10 is an enlarged side elevational view of aportion of the apparatus of Fig. 1 including the pin hole glazing equipment;

' I4 which is driven by the motor and includes a Fig. 11 is an enlarged vertical sectional view of the chuck shown in Figs. 1 and 2;

Fig. 12 is an exploded perspective view, with parts broken away, of the driving and controlling connections of the apparatus; and

Fig. 13 is an elevational view of a portion of' the control mechanism of Fig. 12.

In the drawings is shown apparatus for treating an insulator I such as is shown in Fig. 3 in accordance with the invention. The embodiment illustrated is such as will coat the pin hole of the insulator with glaze to a predetermined height as indicated at a and the outer top surface as at b for a predetermined distance.

Referring now to Figs. 1 and 2, the apparatus includes a conveyor comprising a plurality of cars or trays 2 which are pivotally connected to each other by means of roller pins 4 to form an endless chain. Each of these cars includes wheels or rollers 6 which engage a metal track 8 in the upward portion of their travel. The track-way 8 is secured to base members I by means of a plurality of supporting beams I2. The cars are arranged to be driven by adriving sprocket I4 located at one end of the track while an idler sprocket I6 is located at the other end. The idler sprocket is fixed to a shaft I8 seated in bearing members 20 which are adjustable horidriver pin I6 for engagement between the spokes of the Geneva gear to intermittently drive a shaft 18 to which it is attached. With a Geneva gear having 5 spokes, as shown, it will be evident that its shaft will be rotated through V5 of a revolution for each revolution of, the driv- I each of them will bedriven a predetermined distance during the motion of the sprocket to bring eachcf them, in turn to a predetermined stazontally along a pair of supporting bars 22. This I adjustment is made by means of a. screw .thread- .ed member 24 which is .attached to the bearing 20 and engages threads in a stationary member'26.

Locatednear one end of the conveyor is a pinhole glazing apparatus indicated generally at 28, the operation of which is synchronized with the intermittent movement of the table by means of a pair .of vertical rods 30 and 32. These rods 38 and 40. On the ends of these pushrods-are located at pair of cam followers 42 and 44 which are operated from a conveyor driving disk 46 tionary position. v

Attached to one side of the driving disk .10 is a cam shoe 82 while a cam pin 84 extends further out from the leading edge of this cam shoe. to engage the cam followers42 and 44, respectively to actuate the push rods 38 and 40 in synchronism with the movement of the conveyor.

As is best shown in Fig. 6, the vertical column 64 for the dipping mechanism is secure at its bottom to a metal flange 86 which is in turn attached by any suitable means to a base member88. Disposed within the lower end of this column is a metallic base member 80 having a recess 92 within which is seated the lower end of a cylindrical body 94. A cylinder bonnet 86 having an opening 98 through which a main vertical shaft I00 extends is disposed on the upper end ofthe cylinder while suitable packing means I02 surrounds the shaft at this point. A piston member I04 is secured to the lower end of the shaft I00 to fit snugly within the cylinder while an air-pressure pipe I06 communicates with the "bottom of the cylinder at a point below-the lowermost travelof the piston. The index head 62 is secured to the shaft I00 in a vertically adjustable position between nuts I01 engaging the screwthreaded upper end thereof. Located within iahe upper end of the vertical column 64 is a top bearing support I08 which vertical column intermediate the ends and also in a manner which will hereinafter be explained.

. Located near the driving end of. the conveyor.

is a dipping assembly 58 which includes a Pinrality of angularly spaced arms 60 attached to an index head 62 which is, in turn, supported from a vertical column indicated at 64.' .The index head is adapted to o'peratein synchronism with the conveyor and on the'end of I each of the arms is disposed a chuck 66 for gripping an insulator when it is disposed at, aparticular position of the conveyor. I

Having particular reference to includes a bushing II4 for engaging the shaft I00. A bevel gear I I8 is attachedto the shaft I00 held in the stationary position by means of a bearing spacer I22 which engages the top bearing support at its upper end and is secured at its lower end to a collar member I24. This collar member -I24 engages the gear II6 through a bearing I26.

Having reference also to Figure 12, it will be seen that this gear M6 is engaged by another bevel gear I28 which is secured to a shaft I28 driven from the ft 18 which carries the Geneva gear already desc ibed. In addition, a sprocket wheel I30 is secured'to the driving'disk shaft I4 and engaged by a chain I32 to drive another sprocket member I34. The sprocket I34 is keyed v 7 Figs. 4 and 5,,

the driving sprocket I4is'arranged to be driven The cam shoe and cam pin are disposed I Within each of the trays 2, there is disposed a pair of parallel holes. I42 within one of which is located a support I44. As is best shown in Figure 7, a spindle body ms is disposed within the aperture I42 and secured to the tray by bolts or the like. Within the spindle body are a pair of bushings I48 for engaging a rotatable vertical spindle I50 to which is secured a base member I52 by means of a b01t.l54. To this base is secured a pot or holder body I56 in'any suitable manner, while an adapter member includingan annular body I58 is bolted to the upper end thereof. A rubber pad I60 is preferably cemented to the annular member to prevent injury to the surface .of-anarticle disposed therein.

To the lowerend of the spindle I!) is secured a V-puliey' I6I by means of abolt I62. This pulley is disposed to engage a rubber driver I64 of cooperating shape driven by a motor I66 (Fig.

- 1) when it reaches a predetermined stationary position. The motor I66'is preferably supported directly from the main track supporting structure.-

The pin hole glazing apparatus includes a glaze tank I61 which is best shown in Figs. 8 and 9.

At the lower end of the glaze tank is located a measuring container I68 which communicates therewith through a valve I attached to a valve rod I12. The valve rod- I12 extends through a guide member I14 disposed in the tank and through the top of the tank where it is connected to an operating lever I15, which, in turn, is pivotally secured to the tank at I16. .On the side of this measuring container is/an adjustment cylinder I18 in which is disposed a piston I80, the

position of which may be controlled by a handle I82 to vary the capacity of the measuring unit.

A returnpipe indicated at I84 extends from a lower portion of the measuring container to the I side of the glaze tank at a. point I86 disposed .above the glaze leveltherein as indicated.

. Connected to the bottom of the measuring container through, a glaze yalve I90 is a pipe I92 which forms the inner member of a telescoping tube.. A second tube I94 extends around the pipe I92 in longitudinally movable relationship thereto to complete the telescoping tube. A pair of separable collars I96 and I98 are secured to this outer tube I94 while a. compression spring I99 is disposed therebetween with a seat member 200 at its upper end. An operating plate 202 is-located beneath the collar I96" to engage the spring seat 200 for moving the outer member I94 downwardly along the inner pipe I92 to extend the unit. An operating lever 204 for the valve I90 is secured to the operating plate 202 to open the valve upon' the tube being extended a predetermined amount. In the lower end of the tube I 94 is disposeda valve seat 206 for engagement with, a drop valve 208.

- This drop valve includes a downwardly projecting pin 2I0 andis of such weight that after being opened by being moved upwardly within the tube,

it will automatically close because of its own weight.

As is shown in. Figure 10, the glaze tank I61 is;

mounted in a stationary position of supports 2I2 attached to the track 8, while an air cylinder 2" is similarly supported therefrom. Within the air cylinder is. disposed a, piston 2l6 to which is. at-

tached 'a rod 2I8 connected to the operating- .plate 202; A four-wayval've 220 communicates with a source of air pressure through a pipe 222' while other passages communicate through pipes 224 and 226. respectively, with the upper and lower portion: of the air cylinder 2. an operating lver 228 is arranged to cause communication between pipes 222 and 228while in the substantially horizontal position shown, while it causes the pipe 222 to communicate with the lower portion of the air cylinder through the pipe 224 when in a position displaced substantially 45 degrees counter-clockwise therefrom as shown in the dotted lines. At the end of the lever 228 near v the valve 220 is a downwardly bent portion indi-.

10 cated at 229 which is connected to a spring 280 secured to the framework.

glaze tank 161 and is provided with an operatlever 2 34 which, in the position shown.

compression spring 246 biasing it in a clockwise direction against a stop 248 on the vertical rod to swing the latch 238. Themember is thus adapted, upon upward movement of the rod 30 30 to pivot the latch, 288. in a clockwisedirection and permit the spring230 to swing the-operating lever 228 downwardly to the dotted position against a stopat 250.

A spring 252 extends from an end of the lever I15 to a shaft 254,0n the supporting structatable' link mechanism 256 which is adapted to raise the valve rod I12 to open the valve I10 in response to upward movement of the rod 32.

Also secured to the vertical rod 32 is an operating latch 260 which is adapted to be engaged by a stationary arm '262 upon downward motion of the rod and rotated counterclockwise against the biasing action of a tension spring 264 toengage the portion 229 of the operating lever 228'.

This action results-in moving the lever 228 from its down position to the up position shown. Referring to Figs, 6 and 11, it will be seen that the spindle head 62 includes an annular passage 266" which communicates with the interior of the arms 60 as 'weil as with tubular members 268 whi'ch lead to a vacuum pumpor tank, as indicated. On the endof each ofthe arms, there is disposed a tubular casing .210 which is secured thereto by means of bolts 212 while an apertured baflie member 214 extends therebetween.

A cap portion 216- isfltted over the .top of the casing in sealed relationship while a bushing 0 218 is centrally arranged within it. Within the bushing is located a tubular shaft 280 which is slidably arranged within the casing and includes an axial opening 282 communicating with a radial opening 284. The radial opening is are 65 ranged to communicate with the interior of the bushing-when the shaft tical position.

l2 80 is in an upwardver:

' of the shaft m thereis ee- To the lower end cured a horizontal plate 288to which ;is cemente'd a" soft rubber pad 288.- An aperture is provided in-the pad 288 to permit communica Y I engaged thereby.- A compression spring 280 16 is disposed around the shaft 288 between the Another valve 282 is disposed on' top of the trim to bias the valve rod I12 downwardly to closed position. The shaft 254 is part of a roarm through apertures in the casing andtion of vacuum with the interior of the insulator member 286 and a bottom member 292 attached to the casing 210. In addition, collars 294 and 296 are secured to the shaft 280 to limit respectively the downward and upward motion thereof .posed between the casing and the operating lever to bias the lower portion of the lever including prong 304 inwardly. The prong 304 is adapted to engage either the lower surface of a flange 306 on the member 286 or one-of the annular grooves 308 therein.

Thus when the chuck is moved downwardly so that the rubber pad 288 engages an insulator such/as that indicated at I, the tubular shaft is pushed upward in the casing to bring the opening 284' into communication .with the vacuum source. At the same time, the operating lever, being biased inwardly, grips the flange 306 or one of the grooves 308 therein to lock the shaft 280 in communication with the vacuum source after the chuck unit is moved upwardly and thus hold the insulator thereon. To release the article, it is only necessary to push inwardly on u a knob 3I0 on the operating lever to permit the spring 290 to force the shaft 280 out of 'communication with the vacuum source.

the Geneva gear, the cam shoe 82 engages the cam follower 42 to push the operating shaft 38 to the right, thereby causing upward movement of the rod 30. The lever 242 thus causes ',thelatch 238 to disengage the lever 228, thereby causing the compressed fluid in pipe 222 to communicate with the bottom of air cylinder 2I4 causing the piston 2| 6 to move the telescoping tube upwardly out of the pin pole of the insulator.

At the same time, the raised portion of the cam at which the arm II2 opens thevalve I10.

permit the passage of compressed air into the bottom of the cylinder 94 toraise the index head 62 of the dipping mechanism upwardly and withdraw the insulator Ib from the receptacle 3I2. At the same time another chuck 66c lifts from the conveyor-an insulator Ic which it engaged while the unit 58 was in the downposition.

A short time later, the rod has moved far enough to cause the interior of the receptacle I 61 to communicate with the atmosphere through the valve 232. In the meantime, thecam pin 84 has come into engagement with the cam follower 44 to cause upward movement of the vertical rod 32 for rotating the link 256 to the position The measuring chamber I68 is then immediately filled At a predetermined position along the path of rotation of the arm 60 is disposed a'receptacle 3| 2 for glazing fluid. This receptacle is pro vided with annular overflow chamber indicated at 3 from which fluid may be removed by means of a tube 3I6 to maintain the levelin the receptacle proper constant. At the same time, the interior, passage of a tubular supporting member 320 communicates with the interior of the receptacle 3I 21to permit the pumping of addltional fluid into it from the bottom. In order to prevent undue agitation of the fluid, abaffle plate 322 is disposed over; this lower entrance. The support 320 is screw'threaded and secured .within a bracket 324 attached-to'the stationary part of the apparatus so that the vertical position of the receptacle may readily be adjusted.

The control of the valve I40 for causing vertical movement of the shaft I00 and index head 62 will be readily understood upon reference to Figs.

12 and 13. four-way valve I40 may be of usual construction and in addition to communiwith glazing or coating liquid and the rod 32 moves downward toagain close the valve I I0. While traveling downwardly, however, the rod moves the latch 260 into engagement with the portion of the cylinder 2 I4. This results in downward movement of the rod 2I8 and accordingly,

' of the entire telescoping mechanism.

eating with the pipe I06 which leads to the. air

cylinder 94 has another passage connected with a compressed air source through a pipe 326. The remaining passages are closed by a plug 328 and open to the atmosphere, respectively. An operating link assembly for the valve ispivoted about a fixedpoint 330 and connected to a spring 332 to bias a pin 334 thereon against the surface of the cam. In the embodiment shown the. pipe I06 is open to' the atmosphere when the pin'334 engages the lower cam surface and'is connected to the air pressure pipe 328 when "the pin bears against the raised surface of the cam."

'- The operation of the device may be best exinto the pin hole.

In the meantime, the operating pin 16 has come into engagement with the Geneva gear 12 and the conveyor mechanism has moved the length of one tray so that the next insulator is directly under the telescoping/tube in a stationary position. During the same time the dipping mechanism has been rotated in a counterclockwise direction to bring the next chuck 66d to a position directly above another insulator which has been moved to the stationary position which was primarily occupied by Ic. At-the same time the chuck 66c and article Icare moved to the posi-- tion over the receptacle 3I2.

The downward motion of the operating plate 202 opens the valve I90 to permit the material from the measuring container I68 to enter into the tube portion, and upon the pin 2I0 on the stop valve engaging the bottom of the pin hole, the measured amount of material flows out.

Being longer in operation than the rod'32, the rod 30 is still traveling downwardly during the aforementioned operations and it reaches a position, opening the valve 232 to the vacuum source immediately after the material has been poured With the upper portionof the receptacle I61 at vacuum pressure, the material in the pin hole is then drawn upwardly through the telescoping tube, the'measuring container I68, and through the return pipe I84, into the receptacle. The drop valve 208 closes. itself immediately' upon its pin coming out of contact with the bottom of the pin hole and thus prevents any dripping of material duringremoval of the telescoping tube.

While the driving pin I6 is out of engagement with the Geneva gear the lower portion of the cam I38 engages the pin 334v causing the valve of said coating material from said recess while the "necessary to the invention, it is preferred to provide this rotation since it facilitates drying of the glaze in the pinhole. Further this makes it convenient to adapt the mechanism for stripping or sprayingthe articles with a spray gun, if desired.

It will appear evident that the apparatus may by the chuck directly over the open end thereof is disposed upwardly.

3. A device for coating the inner surfaces of ceramic articles having recesses therein comprising a movable table for supporting a plurality of recessed articles in spaced positions, means f for intermittently driving said table to succes-' sively move each of said articles'to a predetermined stationary position with the open end of the recess disposed upwardly, means for automatically introducing liquid coating material to a, predetermined depth in the recess in an article be readily adapted to handle'articles of various difierent sizes. The position of the index head 62 on the movable shaft 100 may be adjusted by means of the nuts I01 while the vertical position of the glaze tank may be changed through the medium of the bracket support 324. Different sized adapters I58 may be used in the holder units and, if desired the size of the holders themselves may be changed. The chuck units-66' readily accommodate themselves to slight variations in insulators of the same general size because of the grooves 308 thereon. Further, the efiective volume of the measuring cylinder I68 may be varied through the medium of the'adjustment cylinder, I18. The speed of operation -is.controllable in a simple manner while thevarious cams may be designed to provide the most desirable operating cycles;

While only one of the holes I42 in each tray is shown provided with insulator holders and only a single dipping mechanism 58 is employed, it will be evident that this and the pin coating mechanism may be duplicated to simultaneously treat two rows of-insulators. It is also within the scope of the invention that electrical timing and solenoid equipment may be substituted for the mechanical cam arrangements shown to properly control the cycle of operation.

Since these and numerous other modifications may be made without departing fromthe spirit at said predetermined position, and means for automaticallly withdrawing from the recess the portion of the material not adhering to the sur face thereof.

4. A device. for coating the interior surfaces of ceramic articles having recesses. therein comprising a movable member, means'for supporting a plurality of recessed articles on saidrnember in spaced relationship with the open ends of the recesses disposed upwardly, means for intermittently moving said member to move each of said articles successivelyto a pre-determined stationary position, a tubular member, means for moving said tubular member into the recess in an article at said position, means for introduc ing liquid coating material into said recess to a predetermined depth through said tubular member, means for withdrawing from the recess the portion of the material not adhering to the sur- 'face thereof, and means for withdrawing said tube from the recess prior to movement of the article away. from said position.

5. A coating device of the class described comprising a movable table, means, for supporting a plurality of pin type insulators on said table in spaced relationship with the openends of the and scope thereof it isintended that the invention be limited only by the appended terpreted in view of the prior art.

I claim as my invention:

claims inl. A device for coating the inner surface of a ceramic article having a recess therein oomprising a movable member, means for intermit-, tently moving said member, means for supporting a recessed article on said member with the'open end of the recess disposed upwardly when said member is in a predetermined stationary posi-.

tion, means for introducing a predetermined amount of liquid coating material into the recess in the article while at said predetermined position, and means for withdrawing the excess of said coating. material from the recess.

dexing member, means for intermittently moving said member, means for supporting a plurality position, and means for withdrawing the excess forautomaticallywithdrewing said ,2. A coating device comprising a movable insulator from said position.

pin holes disposed upwardly, means for intermittently moving said table to move each of said insulators successively to a predetermined sta-' ,tionary position, a tubular member, means for automatically moving said tubular member downwardly into the pin hole in an insulator at 45 said position, means for introducing a predetermined amount of liquid coating material into said pin hole through said tubular member, means forvautomatically withdrawing the coating material not adhering to the pin' hole surface through said tubular member, and means-for automatically withdrawing said tubular member from the pin hole prior-to movement of the in- 6. A coating device comprising a. movable table, means for maintaining aplurality of articleseach having a recess therein on said .table in spaced relationship with the upper ends of the recesses disposed upwardly, means for intermittently moving said table to'moveeach of said articles successively to a predetermined stationary position, a. tubular member, means for automatically moving saidtubular member intothe recess in each article while at said predetermined po ition, a receptacle for liquid coating material, a. measuring chamber, means for automatically causing periodic communication between said re-.

l ceptacle and said chamber to" fill the chamber of ceramic articles each having a recess therein with coating material, means for automatically introducing the. coiting material from said chamher into the recess in the article through the-tubular member therein, pumping means, means for automatically controlling said pumping means e to withdraw from the recess the coating material adhering to the surface thereon-and means tubular memtubular member while recesses disposed upwardly, means for intermittently driving said table to move each of said articles successively to a predetermined stationary position, a tubular member, means controlled by said driving means for moving said tubular member into the recess in each article while in said predetermined stationary position and for removing it prior to movement of the article away from said position, a receptacle for liquid coating material, a measuring chamber, means controlled bysaid driving means for periodically causing communication between said receptacle and said chamber for a limited time during each movement cycle, to measure a predetermined amount of material in the chamber, means controlled by said driving means for introducing the predetermined amount of coating material from said chamberiinto the recess in thearticle through the tubular member therein, and pumping means controlledby said driving means for withdrawing coating material not adhering to the surface of throughsaid tubular member the portion of said the recess in the article and conducting it back into said receptacle.

8. A coating device comprising a movable table, means for supporting a plurality of similar ceramic articles each having a recess therein on said table inspaced relationship with the open ends of the recesses disposed upwardly, means for intermittently moving said table to move each of said articles successively to a predetermined stationary position, a tubular member including a normally closed valve on the end thereoi which is operable to open position when said member extends into a recess in one of said articles in a predetermined position, means for automatically moving said tubular member into its said predetermined position into the recess of each of said articles while in said predetermined stationary position and for removing it prior to movement of the article away from its said position, means for automatically introducing a predetermined amount of liquid coating material into said recess through said tubular member while in its said predeterminedposition, and means for automatically withdrawing the coating material not adhering to the surface of the recess through said in its predetermined position. t

9. A device 'for coating the inner surface of ceramic articles having recesses therein comprising a movable conveyor member for supporting a plurality of recessed articles in spaced relationship, means driving said conveyor to successively move each of said articles to a predetermined stationary position with the open end of the recess disposed upwardly, meansfor automatically introducing a predetermined amount or liquid coating material into an article at said predetermined position, means for withdrawing from the recess the portion of the material not adhering to the surface thereof, and means for rotating each article when at a position subsequent to said predetermined position. 3 Y

10. Apparatus for applying a coating to a ceramic article having a recess therein comprising a movable member, means for maintaining a plurality of recessed ceramic articles on said meme the recesses disposed upwardly, mean for intermittently moving said member to successively move each-of said articles to each of two predetermined stationary positions, means for automatically introducing a predetermined amount of liquid coating material into the recess of an articl at the first of said predetermined positions and withdrawing therefrom the portion thereof not adhering to the contacted surface, a receptacle for liquid coating material, means for automatically gripping an article while at said sec 0nd predetermined position and removing it from said table to dip it to a predetermined depth in the coating material in said receptacle.

11. Apparatus for applying coating material to a pin type electrical insulator comprising a movablemember, means for maintaining a plurality of pin type insulators on said member in spaced relationship with the open ends of the pin holes disposed upwardly, means for intermittently moving said member to successively move. each of said articles to each of two predetermined stafor intermittently driving it in synchronism with said movable member, a plurality of means on said rotatable member for holding insulators, means for moving said rotatable member when in nonrotating condition to cause one of said holding means to grip an insulator at said second predetermined position and remove it from said mov able member, and means for subsequently dipping the insulator to a predetermined depth in the coating material.

12. Apparatus for-applying coating material to a pin type electrical insulator comprising a movable member, means'for maintaining a plurality of pin type insulators on said member in spaced relationship with the open ends of the pin holes disposed upwardly, means for intermittently moving said member to successively move each of said articles to each of two predetermined stationary positions, means for automatically introducing a predetermined amount of liquid coating material into the pin hole of each insulator while at the first of said predetermined positions and withdrawing therefrom the portion thereof not adhering to the contacted surface, a

receptacle for liquid coating material, a rotatable member, spaced means'on said rotatable member for gripping and holding insulators,

means for intermittently rotating said rotatable member in synchronism with the movement of said movable member to successively'bring each of said holding means over an insulator in said second predetermined position and subsequently to a second rotary position over said receptacle,-

and means for moving said rotatable member wheniin the, non-rotating position to cause the holding means over said second predetermined position to grip the insulator 'thereat and the holding means at said second rotary position to I ber'in spaced relationship with the open ends of 1s mittently moving said member to sumessively move each of said articles to each of two predetermined stationary positions, a tubular member, meansjfor automatically moving said tubular member into the pin hole in each insulator while at the first said predetermined. position and for removing it prior to movement of the insulator away from said'position, means for automatically introducing a predetermined amount of liquid coating material into said pin hole through said tubular member extending thereinto, means for automatically withdrawing the coating material not adhering to the pin hole surface through said tubular member before its withdrawal from the pin holes, a receptacle for liquid coating material, a rotatable member and means for intermittently driving it in synchronism with said movable member, a plurality of spaced means on said rotatable member for gripan article in a predetermined position with the,

open end of the recess extending upwardly, amain receptacle for liquid coating material, a measuring receptacle designed to communicate with-said main receptacle, a first valve for controlling communication between said main receptacle and said measuring receptacle, a-"tele 3 scoping tube communicating with said measurping insulators when'brought into contact there-j .with and holding them, means for moving said rotatable memberwhen in non-rotating position to causeone of said holding means to grip an insulator at said second predetermined position and remove it Irom said movable member and to simultaneously .dip an insulator previously gripped by another of said holding means to a predetermined depth in the material in said receptacle.

1..A device for coating the inrier surface of articles having recesses therein comprising receptacle for liquid coating material, a tube communicating with said receptacle and' insertable into the recess of an article disposed with the open end thereof extending upwardly, means for introducing a predetermined amount of liquid coating material from said receptacle into the recess in the article through said tube, a. passage defining member providing communication being receptacle, a second valve for controlling communication between said measuring receptacle and said. tube, means for extending said telescopifig tube to dispose the end thereof in the recess; of an article at said predetermined position,

means for closing said first valve prior to the extension of said tube, means for maintaining said second valve open while said tube is'in extended position to introduce a predetermined amount of material into the recess from said measuring receptacle, a passage defining member for providing communication between said tube and the upper portion of said main receptacle above the level of theliquid material therein,

and means for reducing the pressure in .the 'receptacle above said liquid to pump the portion of the material in the recess not adhering to the surface thereof throughisaid tube and said pasinto said receptacle.

sage defining member EUGENE H. FISCHER. 

